A double temperature sensor determines the body core temperature of a living being. The double temperature sensor includes a sensor block (2), which on one side carries a first temperature sensor (4) provided for placing on the skin surface and on the other side carries a second temperature sensor (5) spaced from the first. An evaluating unit calculates the body core temperature using the measured values of the first and second temperature sensors. The sensor block (2) is held in a hood-shaped housing shell (1) which is shaped in such a manner that the first temperature sensor (4) on the sensor block and the peripheral outer edge (8) of the housing shell (1) spaced therefrom lie in one plane. When the housing shell (1) is lying on the skin surface, the sensor block (2) is surrounded by an air-filled cavity closed off by the housing shell.
